An engine with a hydraulically-driven variable valve timing mechanism includes an actuator disposed at an end of a camshaft, an actuator oil passage as an operating oil path for introducing oil from an oil pump to the actuator, and a camshaft oil passage as a lubricating oil path for introducing the oil to the camshaft.
Conventionally, an engine comprises structures forming an oil passage for the engine, which include an operating oil path in communication to an end journal at an end of a camshaft in a cylinder head to introduce the oil to an actuator for a variable valve timing mechanism, and a camshaft lubricating oil path in communication to a camshaft housing of a journal adjacent to the end journal.
Also there are some structures of an oil passage for the engine, which include an operating oil path in communication to a camshaft housing journal section of the end journal of the camshaft to introduce the oil to the actuator for the variable valve timing mechanism, and a lubricating oil path also in communication to the end journal of the camshaft.